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81.
The effects of G-CSF and naproxen sodium on the serum TGF-beta1 level and fracture healing in rat tibias 总被引:2,自引:0,他引:2
Local and systemic release of transforming growth factor beta 1 (TGF-beta1) is known to increase during the process of fracture healing and this cytokine stimulates bone healing. The majority of the non steroidal anti inflammatory drugs (NSAIDs) inhibit fracture healing. Granulocyte colony stimulating factor (G-CSF) is a hematopoietic growth factor that stimulates bone marrow. In this study, the effects of the NSAID naproxen sodium, G-CSF, and both of them in combination on the TGF-beta1 serum level in rats with tibia fractures were measured and fracture healing was evaluated by histopathologic and radiologic examination. The TGF-beta1 serum levels obtained on day one (24 h after fracture but before administration of naproxen or G-CSF) were found to be similar in all of the five groups (p > 0.05). At the end of the first week, TGF-beta1 levels were significantly lower in naproxen-treated rats than those of the other groups excluding control (p = 0.002). Similar changes in TGF-beta1 levels were found at the end of the second and fourth weeks. TGF-beta1 levels were significantly higher in G-CSF-treated rats at the end of the first, second and fourth weeks (p < 0.05). Fracture healing scores measured with histopathological and radiological methods were higher in G-CSF-treated rats than in naproxen-treated ones. When both naproxen and G-CSF were given, the scores resumed to normal. The results point to the negative effect of naproxen sodium on fracture healing is due to its decreasing effect on the level of TGF-beta1, which may be a new possible mechanism. Moreover, this negative effect can be inhibited by the use of G-CSF. 相似文献
82.
The combination effects of water stress and gibberellic acid (GA3) on physiological attributes and nutritional status of maize (Zea mays L. cv., DK 647 F1) were studied in a pot experiment. Maize plants were grown in the control (well watered WW) and water stress
subjected to treated both water stress and two concentrations of gibberellic acid (GA3 25 mg L−1, 50 mg L−1). WS was imposed by maintaining the moisture level equivalent to 50 % pot capacity whereas the WW pots were maintained at
full pot capacity. Water stress reduced the total dry weight, chlorophyll concentration, and leaf relative water content (RWC),
but it increased proline accumulation and electrolyte leakage in maize plants and appears to affect shoots more than roots.
Both concentrations of GA3 (25 and 50 mg L−1) largely enhanced the above physiological parameters to levels similar to control. WS reduced leaf Ca2+ and K+ concentrations, but exogenous application of GA3 increased those nutrient levels similar or close to control. Exogenous application of GA3 improved the water stress tolerance in maize plants by maintaining membrane permeability, enhancing chlorophyll concentration,
leaf relative water content (LRWC) and some macro-nutrient concentrations in leaves. 相似文献
83.
Sarikurkcu C Tepe B Daferera D Polissiou M Harmandar M 《Bioresource technology》2008,99(10):4239-4246
This study is designed to examine the chemical composition and in vitro antioxidant activity of the essential oil and sub-fractions of the methanol extract of Marrubium globosum subsp. globosum. The GC and GC-MS analysis of the essential oil were resulted in the determination of 84 components representing 88.2% of the oil. The major constituents of the oil were spathulenol (15.8%), beta-caryophyllene (9.0%), caryophyllene oxide (7.9%), germacrene D (6.5%), and bicyclogermacrene (3.1%). Antioxidant activities of the samples were determined by three different test systems namely DPPH, beta-carotene/linoleic acid and reducing power assay. In DPPH system, the weakest radical scavenging activity was exhibited by the essential oil (1203.38+/-7.18 microg ml(-1)). Antioxidant activity of the polar sub-fraction of methanol extract was superior to the all samples tested with an EC(50) value of 157.26+/-1.12 microg ml(-1). In the second case, the inhibition capacity (%) of the polar sub-fraction of methanol extract (97.39%+/-0.84) was found the strongest one, which is almost equal to the inhibition capacity of positive control BHT (97.44%+/-0.74). In the case of reducing power assay, a similar activity pattern was observed as given in the first two systems. Polar sub-fraction was the strongest radical reducer when compared with the non-polar one, with an EC(50) value of 625.63+/-1.02 microg ml(-1). The amount of the total phenolics was highest in polar sub-fraction (25.60+/-0.74 microg/mg). A positive correlation was observed between the antioxidant activity potential and total phenolic level of the extracts. On the other hand, total flavonoid content was found equal for the both sub-fractions. 相似文献
84.
The manufacture of particleboards using mixture of peanut hull (Arachis hypoqaea L.) and European Black pine (Pinus nigra Arnold) wood chips 总被引:2,自引:0,他引:2
This research was conducted to investigate the suitability of peanut hull to produce general purpose particleboards. A series of panels were produced using peanut hull and mixture of peanut hull and European Black pine wood chips. Particleboards were manufactured using various hull ratios in the mixture (0%, 25%, 50%, 75% and 100%). Urea formaldehyde adhesive was utilized in board production and boards were produced to target panel's density of 0.7 g/cm3. Panels were tested for some physical (water absorption and thickness swelling), chemical (holocellulose content, lignin content, alcohol-benzene solubility, 1% NaOH solubility, hot water solubility and cold water solubility) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties. The main observation was that increase in peanut hull in the mixture resulted in a decrease in mechanical and physical properties of produced panels and panel including 25% hull in the mixture solely met the standard required by TS-EN 312 standard. Conclusively, a valuable renewable natural resource, peanut hull could be utilized in panel production while it has been mixed to the wood chips. 相似文献
85.
86.
Dafna Rozenzvieg Cengiz Elmaci Alon Samach Susan Lurie Ron Porat 《Physiologia plantarum》2004,121(3):421-428
In order to continuously supply horticultural products for long periods, it is essential to store them after harvest in low temperatures. However, many tropical and subtropical fruits and vegetables, such as citrus, are sensitive to chilling. In previous studies, the authors have shown that a short hot water rinsing treatment (at 62°C for 20 s) increased chilling tolerance in grapefruit. In order to gain more insight into the molecular mechanisms involved in heat‐induced chilling tolerance, PCR cDNA subtraction analysis was performed which isolated four different PCR fragments whose expression was enhanced 24 h after the heat treatment, and that showed high sequence homology with various plant HSP18‐I, HSP18‐II, HSP22 and HSP70 genes. It was found that the short hot water treatment given at 62°C for 20 s, but not at lower temperatures of 20 or 53°C, increased the expression of the various HSP cDNAs in grapefruit peel tissue. However, when the fruits were kept at ambient temperatures, the increases in HSP mRNA levels following the hot water treatment were temporary and lasted only between 6 and 48 h. Similar temporary increases in the HSP mRNA levels were detected following exposure of the fruit to a hot air treatment at 40°C for 2 h. Nevertheless, when the fruits were treated with hot water but afterwards stored at chilling temperatures of 2°C, the mRNA levels of the various HSP18‐I, HSP18‐II, HSP22 and HSP70 cDNAs increased and remained high and stable during the entire 8‐week cold‐storage period, suggesting their possible involvement in heat‐induced chilling‐tolerance responses. The chilling treatment by itself increased the expression of the HSP18‐I cDNA, but had no effect on the mRNA levels of any of the other HSP cDNAs. Exposure of fruit to other stresses, such as wounding, UV irradiation, anaerobic conditions and exposure to ethylene, had no effect on the expression of the various HSPs. Overall, the study explored the correlation between the expression and persistence of various HSP cDNAs in grapefruit peel tissue during cold storage, on the one hand, and the acquisition of chilling tolerance, on the other hand, and the results suggest that HSPs may play a general role in protecting plant cells under both high‐ and low‐temperature stresses. 相似文献
87.
Neural tube defects are important causes of infant mortality and childhood morbidity. We investigated the relationship between
zinc, selenium, copper, and lead concentrations and neural-tube-defect occurrence in women with a second-trimester termination
due to fetal-neural-tube defects (NTDs) in this case-control study. Fourteen pregnant women whose pregnancies were terminated
as a result of second-trimester ultrasonographic diagnosis of neural tube defects were recruited as cases. The control group
(n=14) consisted of women who were selected among age-, gravidity-, and socio-economic-state (SES)-matched women who had a normal
triple-screen and targeted ultrasound during the second trimester with documented normal fetal outcome. Zinc and copper determinations
were made using flame atomic absorption spectrophotometer (AAS). Graphite furnace AAS was used for Pb, and Se levels were
measured with hydride generation AAS. Cases had significantly low serum zinc and selenium levels (62.48±15.9 vs 102.6±23.7
and 55.16±11.3 vs 77.4±5.5, respectively, p<0.001). Serum Cu and whole-blood Pb levels were significantly high when compared to controls. There was a negative correlation
between serum zinc and selenium levels, and serum copper levels (r=−425 and −0.443, p<0.05). Our results are consistent with some previous reports. The etiology of NTDs cannot be explained with one strict etiologic
mechanism. On the contrary, an interaction among environmental, genetic, and nutritional factors such as trace elements and
vitamins would explain these anomalies. If folic acid supplementation is given, additional Zn supplementation should be considered
for the further decrease in the recurrence and occurrence of NTDs. 相似文献
88.
Hasan Dursun Aytul Noyan Selcuk Matyar Mithat Buyukcelik Mustafa Soran Nurcan Cengiz Aysun K. Bayazit Gulsah Seydaoglu Gulen Attila Ali Anarat 《Gene》2013
To investigate the association of endothelial nitric oxide synthase gene intron 4 (eNOS4) polymorphisms with nephrotic syndrome, the eNOS4 genotypes were assessed in 161 children with nephrotic syndrome in comparison with 78 healthy subjects. We classified the children with nephritic syndrome into 2 groups: as steroid-sensitive nephrotic syndrome (SSNS) (n = 125) and steroid-resistant nephrotic syndrome (SRNS) (n = 36). The eNOS4 polymorphisms were analyzed by polymerase chain reaction. The frequencies of eNOS4 aa, ab and bb genotypes were 3%, 31%, and 66% in all the nephrotic syndrome groups, and 1%, 23%, and 76% in the control group (x2 = 2.87, p > 0.05). In addition, the frequencies of eNOS4 aa, ab and bb genotypes were 2%, 33%, and 65% in SSNS group, and 5%, 28%, and 67% in the SRNS group (x2 = 1.13, p = 0.567). The present study is the first to investigate eNOS4 gene polymorphisms in children with SSNS and SRNS. Our data show that the eNOS4 gene polymorphisms were not associated with the development, frequent relapse and response to steroid in nephritic syndrome. 相似文献
89.
Kesik V Lenk MK Kurekci AE Acikel CH Akgul EO Aydin A Erdem O Gamsizkan M 《Biological trace element research》2008,123(1-3):168-178
Aspirin is widely used as an antiinflammatory drug especially in children with rheumatic fever arthritis. The diminishing effects of aspirin on antioxidant enzymes and hepato-renal systems at high doses are well-known. It is now evident that the damage at antioxidant system worsens the clinical picture of the disease and prolongs the treatment time. Thus, we investigated the effect of antioxidant enzyme cofactors-zinc and selenium-supplementation on superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels (erythrocyte and liver) and hepato-renal toxicity during aspirin treatment at therapeutic doses. The rats were divided into five groups. The first and second groups were given aspirin 75 mg/kg/day and aspirin plus selenium (Selenium 200, selenium 200 mg tablet as selenium yeast, GNC) and zinc (Zinc 100, zinc 100 mg tablet as zinc gluconate, GNC), respectively, the third and fourth take 50 mg/kg/day aspirin and aspirin plus selenium and zinc twice a day, respectively. The fifth group was control. The rats were treated with aspirin for 5 weeks as in the treatment of rheumatic fever arthritis in children. Erythrocyte SOD and MDA levels were preserved with supplementation, whereas there was no change for GSH-Px levels. Liver SOD, GSH-Px, and MDA levels were not changed. In zinc- and selenium-supplemented groups, the levels of serum alanine aminotransferase, uric acid, and direct bilirubin levels were found statistically decreased compared with nonsupplemented groups. There was no significant histopathologic change in specimens of hepatic and renal tissues. Trace element supplementation may prevent free radical damage and shorten treatment time in children using long-term aspirin treatment. 相似文献
90.
Mehmet Cengiz Baloglu Lutfiye Yildiz Ozer Buket Pirci Gokhan Zengin Abdullahi Ibrahim Uba Yasemin Celik Altunoglu 《化学与生物多样性》2023,20(10):e202300291
Liquidambar orientalis Mill., commonly called the Anatolian sweetgum or Sigla tree, is endemic to southwestern Turkey. It has been historically significant in traditional medicine. In our research, we delved into the therapeutic attributes of its oil, emphasizing its antioxidant, antimicrobial, and antitumor properties. The primary chemical constituent of the gum is styrene, accounting for 78.5 %. The gum demonstrated antioxidant capabilities in several assays, including in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP). It displayed bactericidal actions against various gram-positive bacteria, such as Staphylococcus aureus, and gram-negative strains, including Escherichia coli. Additionally, the oil showcased potent antitumor effects against breast (MDA-MB-231), lung (A549), and prostate (PC3) cancer cell lines. These effects were found to be both time- and dose-dependent. L. orientalis Mill. oil showed the best antitumor activity against breast, lung, and prostate cancer cell lines after the 24 h and 48 h treatment. Its oil might induce autophagy in the PC3 prostate cancer cell line, whereas its cytotoxicity against MDA-MB-231 and A549 cancer cell lines might not be correlated with autophagy or apoptosis pathways. In conclusion, the oil from the Sigla tree offers promising therapeutic potential and warrants further exploration. 相似文献